Margaret Moerchen
Glossary of Terms
Glossary
- Astrobiology
- A hybrid field that investigates the
conditions necessary for extraterrestrial life and the effects of
extraterrestrial environments on living organisms
- The distance from the earth to the sun;
1.49 x 10^11 meters
- The branch of science studying the universe
beyond earth
- A disk of gas, dust, and ice particles
around a star
- A device designed to block out a bright
central source so that a much fainter object nearby can be seen
- A circumstellar disk where the stellar age
exceeds the timescale for expected dissipation of the original dust and
ices; thus the observed material must be replenished through collisions
of planetesimals or sublimation of comets
- The bending of electromagnetic waves, such
as light, by an obstacle in their path
- The rate of flow of energy from a source
- An instrument used to take astronomical images,
as a camera
- One millionth of a meter, a distance unit
- The mid-infrared wavelength regime spans
~8-25 microns, and the two atmospheric windows around 10 and 18 microns
are exploited in ground-based observing
- The physical structure, or shape, of an
object
- A plot of intensity vs. distance from the center
of the object
- Changes in the atmosphere between the observer and
the source, e.g. temperature or water vapor content
- Changes with time in either the observing
system (telescope + camera) or atmosphere that degrade the resolution
of the image
- An instrument used to take spectra of
astronomical objects by dispersing the incoming light with a
diffraction grating or prism
- An optical instrument, usually designed with
mirrors, used to observe faint and distant objects by using a large
aperture (e.g., the mirror) to both collect more light and magnify the
object